The present invention relates to electro-optic modulation devices and methods. More particularly, the present invention provides an improved silicon-based Mach-Zehnder modulator and methods for balancing two Mach-Zehnder arms based on silicon photonic design platform.
Over the last few decades, the use of communication networks exploded. In the early days Internet, popular applications were limited to emails, bulletin board, and mostly informational and text-based web page surfing, and the amount of data transferred was usually relatively small. Today, Internet and mobile applications demand a huge amount of bandwidth for transferring photo, video, music, and other multimedia files. For example, a social network like Facebook processes more than 500 TB of data daily. With such high demands on data and data transfer, existing data communication systems need to be improved to address these needs.
Over the past, high data rate communication has been widely implemented via optical network, in which data signals are carried by laser light that is specifically modulated using various kinds of electro-optic modulators. Mach-Zhedner modulator is a widely used electro-optic modulator often driven by a push-pull driver (or differential driver) for relieving swing voltage requirements and power consumption. For push-pull (or differential) drive, the balance between two Mach-Zehnder phase modulation arms is very important. But the performance of conventional modulator is sensitive to unbalance of two modulation arms caused by implant mask misalignment due to the use of mirror symmetric implant mask and doping profile (i.e. ‘p-n n-p’ or ‘n-p p-n’). Therefore, an improved Mach-Zehnder modulator and methods for balancing two Mach-Zehnder modulation arms based on silicon photonics platform regardless of implant mask misalignment are desired.